1. Field of the Invention:
The present invention relates, in particular but not exclusively, to a multi-mode light-emitting device for underwater applications.
2. Brief Description of the Prior Art:
Related devices have been proposed in the following prior art documents:
More specifically, devices capable of modifying the characteristics of light through reversal of polarity of the power source have been proposed in the prior art. For example, documents U.S. Pat. No. 5,842,777 discloses a device which modifies the intensity or color of the light by reversing the polarity of the power source. Document JP 62071287 also shows a simple circuit responsive to reversal of polarity to illuminate different light sources.
Portable signaling devices with flashing light sources abound. These can be divided into two main categories: (1) light sources which flash in response to wearer""s movements, and (2) light sources whose on-off cycles are driven by an electronic timer circuit.
Documents U.S. Pat. Nos. 5,303,485 and 4,161,018 provide for a signaling light source which flashes intermittently in response to movement. Alternatively, documents U.S. Pat. Nos. 4,812,983 and 4,613,847 provide for a signaling light source which flashes at a constant rate while document U.S. Pat. No. 4,161,018 describes a signaling light source which flashes in a random manner. Finally, document U.S. Pat. No. 4,296,459 provides a hybrid version which is essentially a user selectable combination of both the above.
The prior art has also proposed devices intended to be worn. For example, document U.S. Pat. No. 4,613,847 describes one embodiment in which a signaling light source may be clipped onto a belt. Document U.S. Pat. No. 4,812,953 illustrates a signaling light source which is worn as an arm band while both documents U.S. Pat. Nos. 4,296,459 and 4,161,018 describe light sources to be worn as jewelry. Finally, document U.S. Pat. No. 5,303,485 discloses footwear with flashing light sources.
Moreover, three prior art references disclose portable lights with a light source turned on and off by rotating the head of the light relative to the body. Documents U.S. Pat. Nos. 4,581,686 and 4,531,178 disclose devices equipped with this type of mechanism. Both of these devices operate by interconnecting two concentrically and proximately mounted pieces by means of a thread and rotating the two pieces to bring two surfaces into contact, thereby closing an electric circuit. Furthermore, document U.S. Pat. No. 1,487,983 discloses a system which, although it does not use what is conventionally referred to as a thread to bring the surfaces into contact, does complete the circuit within the battery compartment. However, the grooved surface of the head and raised nipple of the case of document U.S. Pat. No. 1,487,983 work in a fashion which is similar to a thread.
Furthermore, document U.S. Pat. No. 4,531,178 discloses a switch structure suitable for use under water. Both documents U.S. Pat. Nos. 4,531,178 and 5,842,777 disclose a rubber O-ring to seal the cavity formed by screwing the head onto the case.
More specifically, in accordance with the present invention, there is provided a multi-mode light emitting device, comprising:
a light module comprising a light source, a first terminal, a second terminal, and a polarity responsive controller interposed between the light source and the first and second terminals;
a DC power source having a positive terminal and a negative terminal; and
a switch means selectively defining either interconnections between (a) the first and positive terminals and (b) the second and negative terminals, or interconnections between (a) the first and negative terminals and (b) the second and positive terminals;
wherein the polarity responsive controller comprises:
a steady state power supply circuit activated by the interconnections between (a) the first and positive terminals and (b) the second and negative terminals, and supplying, when activated, steady state power from the DC power source to the light source which then produces a steady state light; and
an intermittent power supply circuit activated by the interconnections between (a) the first and negative terminals and (b) the second and positive terminals, and supplying, when activated, intermittent power from the DC power source to the light source which then produces a flashing light.
According to another aspect of the present invention, there is provided a rotatable switch mechanism, comprising:
a hollow casing made of electrically non-conductive material, the hollow casing having a closed bottom and an opening opposite to the closed bottom to define a compartment for a battery pack having first and second terminals;
an electrically conducting contact plate mounted on the closed bottom of the hollow casing for contact with the first terminal of the battery pack;
a hollow cap made of electrically non-conductive material, the hollow cap being threadedly mounted on the open end of the hollow casing and having a tubular wall portion with a distal annular edge, the tubular wall portion of the hollow cap extending inside the hollow casing from the open end to the closed bottom;
an electric load mounted inside the hollow cap, and including a contact for contact with the second terminal of the battery pack;
an electric conductor running from the electric load along the tubular wall portion to reach and cover a portion of the distal annular edge;
whereby rotation of the hollow cap about the hollow casing in a first direction will bring the electric conductor covering the distal annular edge into contact with the contact plate and the first terminal of the battery pack to thereby energize the electric load, and whereby rotation of the hollow cap about the hollow casing in a second direction opposite to the first direction will spread apart the electric conductor and the contact plate to de-energize the electric load.
The above defined structure therefore provides for a solution to the problem of replacing waterproof switches and reed switches commonly used in underwater applications.
According to yet another aspect of the present invention, there is provided a light-emitting device, comprising:
a hollow casing made of electrically non-conductive material, the hollow casing having a closed bottom and an opening opposite to the closed bottom to define a compartment for a battery pack having first and second terminals;
an electrically conducting contact plate mounted on the closed bottom of the hollow casing for contact with the first terminal of the battery pack;
a hollow translucent lens cap made of electrically non-conductive material, the hollow lens cap being threadedly mounted on the open end of the hollow casing and having a tubular wall portion with a distal annular edge, the tubular wall portion of the hollow lens cap extending inside the hollow casing from the open end to the closed bottom;
a light source mounted within the lens cap and comprising a first contact for contact with the second terminal of the battery pack and a second contact including an electric conductor running from the light source along the tubular wall portion to reach and cover a portion of the distal annular edge;
whereby rotation of the hollow lens cap about the hollow casing in a first direction will bring the electric conductor covering the distal annular edge into contact with the contact plate and the first terminal of the battery pack to thereby energize the light source, and whereby rotation of the hollow cap about the hollow casing in a second direction opposite to the first direction will spread apart the electric conductor and the contact plate to de-energize the light source.
According to a final aspect of the present invention, there is provided a multi-mode switch mechanism, comprising:
a load module;
a DC power source for the load module;
a polarity reversing means changeable between a first mode in which connections of a first polarity are established with the DC power source and a second mode in which connections of a second polarity opposite to the first polarity are established with the DC power source;
a user activated switch having an on position and an off position;
a water activated switch;
wherein the polarity reversing means, user activated switch and water activated switch define between the DC power source and the load module a switching arrangement in which:
when the polarity reversing means is in the first mode, current from the DC power source is supplied to the load module through the user activated switch in the on position; and
when the polarity reversing means is in the second mode, current from the DC power source is supplied to the load module through the water activated switch coming into contact with water.
The foregoing and other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of a preferred embodiment thereof, given by way of example only with reference to the accompanying drawings.